设计一个9V直流稳压电源电路。要求输入电压为工频220V交流电，变压器降压、桥式整流、电容滤波、W317集成块稳压。
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设计一个±5V直流稳压电源电路。要求输入电压为工频220V交流电，变压器降压、桥式整流、电容滤波、集成块稳压。
Please choose the best English to match with the Chinese statements.他们住在多布斯费里镇，与相邻的斯卡斯代尔镇布局凌乱的大型宅邸相比，这是一个相对多样化的社区，这里的居民思想开放、心胸宽广，并引以为豪。
A. Compared to neighboring Scarsdale, with its rambling mansions, Dobbs Ferry is a relatively different community, which pride themselves on the open-mindedness of its population.
B. Compared with neighboring Scarsdale, with its rambling mansions, Dobbs Ferry is a relatively different community, which prides itself on the open-mindedness of its population.
Compared to neighboring Scarsdale, with its rambling mansions, Dobbs Ferry is a relatively diverse community, which pride itself in the open-mindedness of its population.
D. Compared with neighboring Scarsdale, with its rambling mansions, Dobbs Ferry is a relatively different community, which pride themselves in the open-mindedness of its population.
Please choose the best English to match with the Chinese statements.这个地方在马克·扎克伯格离开家的十年间几乎没发生什么变化。马克先上了寄宿学校，后来去了哈佛大学。在那里，他创建了那个改变世界的网络公司，很快就把整个扎克伯格家族变成了深不可测的巨富。
A. The place has changed little in the decades since Mark Zuckerberg left home, first for boarding school and then for Harvard, where he founded the world-altering web company that will soon make the entire Zuckerberg family inexplicably rich.
B. The place has changed a little in the decade since Mark Zuckerberg left home, first for boarding school and then for Stanford, where he founded the world-altering web company that will soon make the entire Zuckerberg family unfathomably rich.
C. The place has changed little in the decade since Mark Zuckerberg left home, first for boarding school and then for Harvard, where he founded the world-altering web company that will soon make the entire Zuckerberg family inexplicably rich.
D. The place has changed few in the decades since Mark Zuckerberg left home, first for boarding school and then for Harvard, where he founded the world-altering web company that will soon make the entire Zuckerberg family unfathomably rich.
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